Abs to Smooth Muscle, Endothelium?

Hello, group.
I am trying to use immunohistochemistry to identify and quantify smooth
muscle cells and endothelial cells and macrophage in mouse arteries, and
am fishing for suggestions for antibodies to use.
For smooth muscle, I have been using Dako's antibofy IA4 against smooth
muscle actin. I am surprised to find that it nicely stains arterioles in
Acetone postfixed frozen sections of mouse heart, but does not stain the
media of mouse carotid arteries. Any ideas?
For endothelium, I have been using Pharmingen's anti CD31 (PECAM-1). Same
story as the IA4--stains in one tissue, but not the other.
I wondering if this could be an effect of the length of time my sections
have been stored at -80C. Either that, or the antigens are different in
the arteries.
Macrophage: Tried MOMA-2, F4/80 without much success. Gosh, it's a heck
of a thing when we can't do something as basic as immunostain macrophages
in mice.
Any suggestions for good antibodies, fixation protocols, etc. will be
received most gratefully.
Thanks,
Jerry Ricks
Research Technologist
University of Washington
Dept. of Pathobiology